Terahertz (THz) electromagnetic radiation has recently found increasing prominence in various fields of science and technology, including identification of biological microspecies, communications for which an increase of several orders of magnitude in bandwidth (as compared with current wireless technology) is required, and identification of metal objects of millimeter size. One of the major obstacles preventing widespread applications of terahertz technology is the lack of powerful tunable sources and sensitive detectors in this frequency regime of the electromagnetic spectrum.
U.S. Pat. No. 5,914,497 discloses an electromagnetic wave detector made of a semiconductor material with a quantum well structure. Detection is based on the effect of changing resistance of electron transport through quantum wells due to absorption of THz photons between two levels of quantum wells, due to the electron population inversion. The detector requires cooling to temperatures of about ten degrees Kelvin.
U.S. Pat. No. 5,729,017 discloses a device which uses electric field interaction with optical beams in biased metal semiconductor microstructures.
U.S. Pat. No. 5,894,125 uses femtosecond pulse laser for excitation of THz radiation.
The present invention provides a novel radiation detector in the terahertz region of the electromagnetic spectrum.